Just do what the majority of the population does, use these criteria:
best hair
easiest name to spell and pronounce
nicest signs and bumper stickers
most signs and bumper stickers - a sign that more people like so and so
vote for who you heard is in the lead, so you can rejoice in having picked the winner (like a horserace)
first name on the ballot
straight party-line (vote for everyone in a certain party)
If anyone doubts that the above is true, I'll concede that it's not true for some offices, particularly president. You can't avoid information on who's running for president.
But, the other 20 offices you're voting for... you have to actively look for information to distinguish between/among the candidates.